1. Field of the Invention
The present invention relates to an image forming apparatus such as a printer and to a self-diagnosis system.
2. Related Background Art
In recent years, the development of image forming apparatuses such as electrophotographic apparatuses having a higher operating speed and higher image quality and capable of multicolor image forming has been advanced and various types of printers are now being put on the market.
With the expansion of the market, an increasing number of requirements have been imposed on the design of printers with respect to the number of functions, performance, image quality, and environmental friendliness. The difficulty of providing printers optimized in every respect under such requirements is also being increased.
In the color printer market, the proportion of in-line machines in which a plurality of electrophotographic units for forming color images in different colors are arranged in series and are simultaneously driven to form an image is increasing. While such machines are capable of multicolor image forming at a high speed and can satisfy the needs of a great number of users, technical difficulty with such machines is becoming more considerable because of many electrophotographic parts and parameters used therein.
Electrophotographic techniques entail a problem in that it is extremely difficult for a user to ascertain a cause of an image defect which occurs in an electrophotographic image forming process, and to thereafter perform proper steps to solve the problem of image defect, because special means including static electricity is used in the image forming process.
Also, it is difficult for a service person to obtain adequate information on electrophotographic conditions at the time of occurrence of an image defect, to which various parameters relate. Even when the service person comes to the place where the image forming apparatus is installed, he or she cannot reproduce the defect with reliability. Thus, in actuality, it is extremely difficult to cope with image defects on the market.
Therefore, in many cases, service operations on image multicolor printers at the time of occurrence of image defects are not done satisfactorily for users, resulting in serious complaints from the users.
Moreover, by considering such complaints, service persons often replace parts or a main unit, even if the replacement is not actually necessary, because it is difficult to ascertain the cause. Thus, an increase in service cost results.
Ordinarily, most of the causes of image defects in an image forming apparatus are incompatibilities between electrophotographic image forming conditions set on the maker side and operating and environmental conditions on the user side, and degradation or malfunctions of electrophotographic parts including toner and a photosensitive drum. If correct information about these conditions can be obtained, it is possible to solve the problem by locating a malfunctioning portion and designating an replaceable part, or by designating a setting according to the operating and environmental conditions on the user side.
However, electrophotographic parameters are ordinarily expressed in voltage or current values which are not easily understandable by users. It is substantially impossible to expect user""s understanding and determination of such parameters. Also, service persons cannot access such information unless they are on the site. Therefore it is presently difficult to use the method of changing electrophotographic parameters as an effective solution.
Further, electrophotographic parameters, large in number, are also related closely to each other. In most cases, it is ineffective to change only one parameter in correcting a malfunction or the like. On the contrary, the system may be unbalanced by changing only one parameter. In such a case, a different problem may arise as a problem of a secondary fault. The difficulty in changing electrophotographic parameters on site of the user is increased by such a secondary fault.
In view of the above-described circumstances, an object of the present invention is therefore to provide an image forming apparatus and a self-diagnosis system suitable for grasping conditions relating to electrophotographic parameters in engines of image forming apparatuses on the market, and for reducing customer complaints.
To achieve the above-described object, according to one aspect of the present invention, there is provided an image forming apparatus capable of one of displaying and outputting of electrophotographic parameters.
According to another aspect of the present invention, there is provided a self-diagnosis system including analyzing conditions in electrophotographic units in the above-described image forming apparatus on the basis of electrophotographic parameters. The parameters include an electrifying condition, an exposure condition, development conditions including a developing bias, a transfer condition, an adsorbing condition, fixing conditions including a fixing temperature, information on physical properties of electrophotographic parts, information on a temperature in the apparatus, and image density information. The system also enables the electrophotographic parameters to be changed according to the results of the analysis on the basis of an instruction from a user or a service person or on the basis of data sets each formed of a plurality of electrophotographic parameters.
According to still another aspect of the present invention, there is provided a self-diagnosis system including means for transmitting electrophotographic parameters determined by an electrophotographic engine to a formatter through a video interface or for transferring the electrophotographic parameters from the formatter to a host computer, a computer in a service center, or the like through a telephone line or the Internet.
These and other objects, features and advantages of the present invention will become apparent from the following description of embodiments of the invention in conjunction with the accompanying drawings.